These common heterocyclic compound, 82560-12-1, name is 3-Amino-5-tert-butylpyrazole, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. name: 3-Amino-5-tert-butylpyrazole
3-Tert-butyl-1 H-pyrazol-5-amine (J-lll) (1 eq., 40 g) was dissolved in dilute HCI (120 ml of HCI in 120 ml of water) and mixed dropwise with NaNO2 (1.03 eq., 25 g in 100 ml) at 0 – 5 C over a period of 30 min. After stirring for 30 minutes, the reaction mixture was neutralised with Na2C03. A diazonium salt obtained by reaction of KCN (2.4 eq., 48 g), water (120 ml) and CuCN (1.12 eq., 31 g) was added dropwise to the reaction mixture within 30 min and the mixture was stirred for a further 30 min at 75 C. After complete reaction, the reaction mixture was extracted with EE (3 x 500 ml), the combined organic phases were dried over sodium sulphate and the solvent was removed under vacuum. The purification (Si02, 20 % EE/hexane) of the residue by column chromatography produced a white solid (J- IV) (6.5 g, 15.1 % yield).
The synthetic route of 3-Amino-5-tert-butylpyrazole has been constantly updated, and we look forward to future research findings.
Reference:
Patent; GRUeNENTHAL GMBH; FRANK, Robert; CHRISTOPH, Thomas; LESCH, Bernhard; LEE, Jeewoo; WO2012/62462; (2012); A1;,
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